An Adaptive Nonlinear Extended State Observer for the Sensorless Speed Control of a PMSM

Abstract

This paper presents a sensorless speed control strategy for a permanent-magnet synchronous motor (PMSM) based on an adaptive nonlinear extended state observer (ANLESO). In this paper, an extended state observer (ESO), which takes back-EMF (back electromotive force) as an extended state, is used to estimate the rotor position and the rotor speed because of its simpler structure and higher accuracy. Both linear ESO (LESO) and nonlinear ESO (NLESO) are considered to estimate the back-EMF of PMSM, and NLESO is finally implemented due to its obvious advantage in convergence. The convergence characteristics of the estimation error of the observer are analyzed by the Lyapunov theory. In order to take both stability and steady-state error into consideration, an adaptive NLESO is proposed, which adaptively adjusts the parameters of NLESO to a compromised value. The performance of the proposed method was demonstrated by simulations and experiments.

Partial observer canonical form for multi-output nonlinear forced system: a new method

“…Generally speaking, the actual industrial plants, especially the major equipment used in basic manufacturing, such as Tunnel Boring Machine (TBM) (Yang et al, 2019;Li et al, 2010;Zhao et al, 2015) and PMSM, often have strong nonlinear characteristics. Therefore, the study of nonlinear system state estimation has been a hot topic during the past several decades (Elbuluk and Li, 2003;Hicham et al, 2004;Gan and Wang, 2015;Liu, 2018).…”

“…POCF is a quasi-linearization system which decomposes the system into an observable subsystem and an unobservable subsystem, and the observable subsystem takes the form of OCF. Both of OCF and POCF are widely used in industrial plant, not only in PMSM (Elbuluk and Li, 2003;Gan and Wang, 2015) but also in sensor networks (Xu and Wang, 2019;Wang, 2020, Xu et al, 2020a, c). But up to now, the POCF of multi-outputs forced system has not been documented.…”

Rotor speed, load torque and parameters estimations of a permanent magnet synchronous motor using extended observer forms

“…However, the control of the PMSM is a complex task due to the presence of nonlinearities in its model, load torque perturbations and wear occurring in mechanical sensors. This leads to, inter alia, to the development of sensorless control method which can be represented by three main approaches: the first one is based on back-emf technique (see [37], [35], [17]) whose advantage is the simplicity of implementation. However, it should be avoided in low speed region because on one hand, the velocity and the flux estimation are sensitive to the stator resistance and on the other hand, the noise amplitude is higher than back-emf.…”

A Soft Sensor Development for the Rotational Speed Measurement of an Electric Propeller

“…This method is based on the model reference adaptive identification to achieve moderate bandwidth speed estimation, but it has also shown some limitations in accuracy at a low speed range [10]. The soft sensors based on various observers, such as an adaptive sliding mode observer [11], an adaptive nonlinear state observer [12], an extended Kalman estimator [13], and a nonlinear observer [14], can be particularly useful for solving rotational speed measurement problems. Nevertheless, they easily fail to achieve a satisfactory performance at a low speed range or in the presence of parametric uncertainties, and some of them are also largely dependent on varies kind of information which cannot be detected easily.…”